An anti-piracy check for Microsoft Windows is causing problems for some users who are being told their copies of operating system XP are not genuine. The tool, called Windows Genuine Advantage, is aimed at cracking down on millions of illegal copies of Windows XP in circulation. Update: Microsoft isn't the only one phoning home without consent: Apple does it too since 10.4.7. The goal is a little less disturbing (to check whether Widgets are up-to-date); however, it cannot be turned off.